Fluid pressure one way jar



June 6, 1961 Filed March 26, 1959 D. D. WEBB FLUID PRESSURE ONE WAY JAR 2 Sheets-Sheet 1 mvENToR D5/eea .Q l/l/E ATTORNEY June 6, 1961 D. D. WEBB FLUID PRESSURE ONE WAY JAR 2 Sheets-Sheet 2 Filed March 26, 1959 INVENTOR Mgg WMM/JM.

ATTORNEY 2,937,129 FLUE PRESSURE ONE WAY .IAR Derrel D. Webb, Houston, Tex., assigner to Houston Engineers, Inc., Houston, Tex., a corporation of Texas Filed Mar. 26, 1959, Ser. No. 802,253 4 Claims. (Cl. 175-297) This invention relates to well tools primarily for use in relatively deep wells and more particularly to a tool which may be lowered into a well and utilized to impart an upward shock or impact to a pipe string or other tool jammed in the well in order to free the same and permit recovery.

Heretofore, various types of impact tools or jars have been proposed and utilized to free tools or other devices jammed in a well and permit recovery of same and certain of these prior art devices have incorporated means for compressing a fluid within the device and suddenly releasing such pressure to permit engagement of impact surfaces thereby providing an upward shock or impact which is transmitted to the tool or pipe string jammed in the well to free the same. These prior art devices utilizing uid pressure have been relatively complex and have also been designed in such a manner that the interioi of the device is substantially completely lled with mechanism thereby preventing the provision of an axial passage through which a wire line may be passed in order to carry on operations in the well below the jar. The design of these prior art tools has also necessitated a relatively large outside diameter which limits the use of the same to wells having a relatively large bore and consequently, a jar of relatively small outer diameter and providing a relatively large central axial passage which may be utilized for various purposes represents a substantial step forward in the art.

It is accordingly an object of the invention to provide a lluid pressure one way jar type well tool which may be lowered into a well and coupled to a pipe or tool jammed therein in relatively close proximity to the point where the tool or pipe is jammed to permit the application of an upward shock or impact substantially directly thereto without loss of impact force due to absorption in a relatively long pipe or drill string.

Another object of the invention is the provision of a fluid pressure one way jar type well tool which may be attached to a pipe or drill string and to a tool or pipe to be recovered from a well without necessitating any modification whatsoever of the pipe or drill string or conventional well tools and in which the tool of this invention is completely self contained thereby requiring no auxiliary equipment.

A further object of the invention is the provision of a uid pressure one way jar type well tool incorporating a cylinder and a piston movable in such cylinder and in which initial movement of the piston operates to compress a iluid in the cylinder until upon reaching a predetermined point in the travel of the piston, the pressure is suddenly reduced to permit relatively rapid movement of the piston in the cylinder.

A still further object of the invention is the provision of a fluid pressure one way jar type well tool incorporating a cylinder and a piston movable in such cylinder and in which initial movement of the piston operates to compress a uid in the cylinder until upon reaching a predetermined point in the travel of the piston, the pressure is suddenly reduced to permit relatively rapid movement of the piston in the cylinder and in which means is provided to transmit torque through the outer stationary parts of the tool, thereby relieving the piston and associated internal parts from torque stresses.

Another object of the invention is the provision of a fluid pressure one way jar type Well tool utilizing a States Patent C) Y portion of the tool with the piston and cylinder which is operable to initially build up a fluid pressure and suddenly release the same, there being a relatively large centrally disposed axial passage extending through the entire tool to permit passage of a wire line or other operating mechanism therethrough for any desired purpose.

A further object of the invention is the provision of a uid pressure one way jar type well tool having a minimum outer diameter and provided with a relatively large centrally disposed axial passage extending entirely through the tool.

Further objects and advantages of the invention Will be apparent from the following description taken in conjunction with the accompanying drawing wherein:

FIG. la is a longitudinal sectional view of the upper portion of a tool constructed in accordance with this invention and with the parts in the position occupied prior to operation of the tool;

FIG. 1b a longitudinal sectional view showing the intermediate portion of the tool including the piston and cylinder;

Fig. 1c a longitudinal sectional View showing the lower portion of the tool;

FIG. 2a a longitudinal sectional View similar to FIG. la but showing the parts in the position occupied upon the completion of the operation of the tool;

FIG. 2b a longitudinal sectional view of the intermediate portion of the tool and with the parts in the final operative position;

FIG. 2c a longitudinal sectional view of the lower parts in tinal operative position;

FIG. 3 a sectional view taken substantially on the line 3-3 of FIG. la;

FIG. 4 a sectional view taken substantially on the line 4-4 of FIG. 1b;

FIG. 5 a sectional view taken substantially on the line 5-5 of FIG. lb; and

FIG. 6 a fragmentary longitudinal sectional view of the piston and cylinder and showing the piston ring in the position occupied during downward movement of the piston in the cylinder.

With continued reference to the drawing, there is shown a fluid pressure one way jar type well tool constructed in accordance with this invention and which comprises an upper elongated tubular member 10 providing a torque barrel, a cylinder 11 removably secured to the barrel 10 by screw threaded means or the like 12 and an elongated sleeve 13 secured to the lower end of the cylinder 11 by screw threaded or other suitable means 14, the sleeve 13 being provided at the lower end with a tapered screw threaded portion 15 for facilitating attachment of the tool to a well device such as a conventional well tool or a pipe or drill string.

The torque barrel 10 is provided inwardly of the upper end thereof with a reduced portion 16 which serves to provide a downwardly facing impact surface 17. The inner wall of the reduced portion 16 is provided with a plurality of axial grooves 18 and these grooves are open at their upper ends and terminate at their lower ends in a shoulder 19. As best shown in FIGS. la and 3, pins 20 are partially received in the grooves 18 and the lower ends of the pins 20 engage the shoulder 19 while the upper ends of the pins 20 are engaged by the lower end 21 of a tubular nut 22 threadedly received in the upper end of the torque barrel 10 as clearly shown at 23 in FIG. la. The nut 22 serves to retain the pins 20 in the grooves 18 for a purpose to be presently described.

A hollow torque mandrel 24 is slidably received in the torque barrel 10 and the mandrel 24 is provided Vwith elongatedgrooves 25 inthe outer surface thereof par.- tially receiving the pins 20 and as clearly shown in FIGS.

la and 3, the pins 20 serve as keys to prevent rotation of the mandrel 24 with respect to the barrel 10 but vpermits sliding movement of the mandrel 24 with respect to the barrel 10. The upper end 26 of the mandrel 24 is provided with a tapered threaded socket 27 for facilitating attachment of the mandrel 24 to a drill or pipe string and also the mandrel 24 is provided with a passage 28 extending axially therethrough.

A tubular connecting rod 29 is secured to the lower end of the mandrel 24 by screw threaded or other suitable means 30 and as clearly shown in FIG 1b, the connecting rod 29 extends downward through a packing gland 31 in the upper end of the cylinder 11. A packing nut 32 is threadedly received at 33 in the upper end of the cylinder 11 and serves to retain the packing gland 31 in assembled condition and is also removable to permit renewal of the packing or other parts of the gland 31. The packing gland 31 serves to prevent leakage of uid from the cylinder 11 to the interior of the torque barrel 10. The upper end of the connecting rod 29 is provided with an enlarged hammer portion 34 disposed in the barrel and providing an upwardly facing striking surface 35, the purpose and operation of which will be later described. Vent apertures 36 are provided in the lower end of the barrel 10 to drain fluid therefrom and prevent movement of the hammer portion 34 in the barrel 10 from acting as a piston to compress fluid within the barrel 10. The connecting rod 29 is also provided with an axial passage 37 extending therethrough in communication with the passage 28 in the mandrel 24.

A piston 38 is disposed in the cylinder 11 and is connected to the lower end of the connecting rod 29 by screw threaded or other suitable connecting means 39. Depending from the piston 38 is an elongated tubular guide member 40 which projects downwardly through a uid tight packing 41 in the upper end of the sleeve 13 and the tubular guide member 40 terminates within the sleeve 13 as clearly shown in FIG. 1c. lIhe tubular guide member 40 and the piston 38 are provided with an axial passage 41a communicating with the passage 37 in the connecting rod 29 and as clearly shown in FIG. 1c, the passage 41a is open at the lower end of the tubular guide member 40.

As best shown in FIGS. lb and 6, the piston 38 is provided with an annular shoulder 42 and spaced above the shoulder 42 are a plurality of annularly spaced abut- -ments 43. A piston ring 44 having a split 45 therein is disposed on the piston 38 between the shoulder 42 and abutments 43 and the piston ring 44 engages the inner wall 45a of the cylinder 11. The piston ring 44 is split in order that the ring may be mounted on the piston 38. A plurality of axially disposed grooves 46 are provided in the piston 38 inwardlyof the piston ring 44 and as clearly shown in FIGS. lb and 6, these grooves 46 extend from the upper surface of the shoulder 42 to a point 47 above the abutments 43. The purpose of these grooves 46 as well as the split 45 in the piston ring 44 will be later described. The piston 38 disposed in the cylinder 11 serves to provide a chamber 48 below the piston 38 and a chamber 49 above the piston 38. Also as clearly shown in FIGS. 1b and 4, the inner wall 45a of the cylinder 11 is provided with a plurality of annularly spaced axially extending grooves `50 which extend from the upper end of the cylinder 11 to a point intermediate the length thereof. The purpose and operation of the grooves 50 will be presently described.

In operation and assuming the cylinder 11 to be filled with a suitable light Weight fluid, the torque mandrel 24 is attached to the lower end of a drill or pipe string by means of the screw threaded connecting means 27 and the sleeve 13 at the lower end of the tool is connected to a tool or pipe string which is to be recovered from a well by means of the screw threaded connection on the lower end of the sleeve 13. YAt this time lthe parts of the device of this invention are in the position shown in FIGS. la, lb and lc and as indicated, the piston 38 is in the lower end of the cylinder 11. Upon exerting an upward pull on the torque mandrel 24 by means of the pipe or drill string attached thereto, the piston 38 is moved upwardly in the cylinder 11 and fluid disposed in the chamber 49 above the piston 38 will be cornpressed as the piston moves upward since the piston ring 44 is in engagement with the upper surface of the shoulder 42 as clearly shown in FIG. lb, and the piston ring 44 in this position operates as a valve to prevent ow of lluid from the chamber 49 above the piston 38 to the chamber 48 below the piston 38. However, since the iluid in the chamber 49 is comparatively incompressible, the outer wall of the chamber 49, i.e., the cylinder 11, due to the enormous pressure that is built up, expands slightly and this serves to slowly bleed the fluid from above the piston 38 in chamber 49 to the chamber 48 below the piston 38, thereby permitting continued upward movement of the piston 38 even though the fluid in the chamber 49 above the piston 38 becomes compressed to the fullest extent possible. Relatively slow upward movement of the piston 38 will continue until the piston ring 44 reaches the lower ends of the grooves 50 in the inner wall 45a of the cylinder 11 and during this movement the fluid will be compressed to an extent suflicient to accumulate a relatively large quantity of energy in the drill or pipe string above the tool and upon the piston ring 44 reaching the lower ends of the grooves 50, the uid pressure above the piston 38 will be suddenly released due to the bypassing of such iluid around the piston ring 44 into the chamber 48 below the piston 38 and this sudden release of iiuid pressure will result in a sudden release of the energy accumulated in the pipe or drill string thereby causing rapid upward movement of the mandrel 24, the connecting rod 29 and the piston 38 and such rapid upward movement will terminate with the engagement of the striking surface 35 on the hammer portion 34 with the impact surface 17 on the reduced portion 16 of the barrel 10 and such impact will result in applying an upward jarring force to the well device connected to the lower end of the sleeve 13. Also, if desired, a torque may be applied to the torque mandrel 24 and such torque will be transmitted through the pins 20 to the cylinder 10 and downwardly through the sleeve 13 to the well device jammed in the well to assist in releasing the same for recovery. It is to be noted that such torque is transmitted solely through the torque mandrel 24, the cylinder 10 and the sleeve 13 and that the connecting rod 29, piston 38 and tubular guide member 40 are not subjected to such torque.

Upon completion of the upward movement of the piston 38 and hammer portion 34 to impart a jarring force to the device to be freed from the well, the elements of the device may be returned to initial position for repeating the operation by lowering the drill or pipe string and torque mandrel 24 which results in moving the piston 38 downwardly in the cylinder 11 and during such downward movement, the piston ring 44 will move upwardly into engagement with the labutments 43 as clearly shown in FIG. 6 and in this position fluid in the chamber 48 below the piston 38 may ow upwardly through the grooves 46 into the chamber 49 above the piston 38 and upon reaching the lowermost position in the cylinder 11, the piston ring 44 will move downwardly into engagement with the upper surface of the shoulder 42 to again operate as a valve and prevent flow of uid from above the piston 38 to the chamber 48 below the piston 38.

It is to be noted that there is a continuous axial passage through the entire tool provided by the passage 28 in the mandrel 24, the passage 37 in the connecting rod 29 and the passage 41a in the tubular guide member 40 and this passage provides communication between the upper and lower ends of the tool of this invention and permits operations to be carried, on below the tool by means of a wire or other line passing through the passage in the tool. It is further to be noted that since there is no torque transmitted through the internal parts of the device of this invention that the passage through the tool may be of relatively large diameter and furthermore, since the outer diameter of the connecting rod 29 and the outer diameter of the tubular guide member 40 are the same, the sum of the volume in the cylinder above the piston 38 and the volume in the cylinder below the piston 38 remains constant regardless of the position of the piston in the cylinder 11 and this arrangement operates to provide a balanced iiuid pressure system within the tool of this invention.

It will thus be seen that there has been provided by the above described invention a relatively simple yet fully operable fluid pressure one way jar which due to the design thereof may be provided with an inner axially extending passage of maximum `diameter `and a minimum outer diameter for the tool and furthermore, due to the design of the piston and piston ring, a relatively light pressure duid may be utilized and furthermore, a balanced pressure system within the tool is provided.

It will be obvious to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the invention isV not limited by that which -is shown in the drawing and described in the specification, but only as indicated in the appended claims.

What is claimed is:

l. A uid pressure one way jar comprising an upper elongated tubular member providing a torque barrel, a cylinder removably secured to the lower end of said barrel, an elongated sleeve secured to the lower end of said cylinder, means on the lower end of said sleeve for attaching the same to a well device, a reduced portion in the upper end of said barrel providing a downwardly facing impact surface, a plurality of axial grooves in the inner wall of said reduced portion, said grooves being open at their upper ends and terminating at their lower ends in a shoulder, pins partially received in said grooves with their lower ends engaging said shoulder, a tubular nut threadedly received in the upper end of said barrel and engaging the upper ends of said pins to retain the same in said grooves, a hollow torque mandrel slidably received in said barrel, elongated grooves in the outer surface of said mandrel partially receiving said pins, said pins preventing rotation of said mandrel with respect to said barrel, means on the upper end of said mandrel for attaching the same to a drill string, a tubular connecting rod secured to the lower end of said mandrel and extending downwardly into said cylinder, a packing gland in the upper end of said cylinder slidably engaging said rod, an enlarged hammer portion on the upper end of said rod in said barrel providing an upwardly facing striking surface, vent apertures in the lower side wall of said barrel, a piston secured to the lower end of said rod and slidably received in said cylinder, an elongated tubular guide member on said piston extending downwardly into said sleeve, packing means in the upper end of said sleeve slidably engaging said guide member, an annular shoulder on said piston, annularly spaced abutments on said piston axially spaced above said shoulder, a split piston ring on said piston movable between said annular shoulder and said abutments and engaging the inner wall of said cylinder, axially disposed groovesl in said piston inwardly of said ring and extending from said shoulder to a point above said abutments and axially disposed grooves in the inner wall of said cylinder extending from a point intermediate the length of said cylinder to the upper end, whereby upon application of an upward force to said mandrel said piston will move upwardly in said cylinder to compress fluid in said cylinder above said piston ring and accumulate energy in the drill string and upon said piston ring reaching the grooves in the cylinder wall pressure in the upper portion of said cylinder will be suddenly released thereby releasing the energy accumulated in the drill string to cause rapid upward movement of said hammer portion and engagement of said striking surface with said impact surface to apply an upward jarring force to a well device secured to said sleeve.

2. A lluid pressure one way jar comprising an upper elongated tubular member providing a torque barrel, a cylinder removably secured to the lower end of said barrel, an elongated sleeve secured to the lower end of said cylinder, means on the lower end of said sleeve for attaching the same to a well device, a reduced portion in the upper end of said barrel providing a downwardly facing impact surface, a plurality of axial grooves in the inner wall of said reduced portion, pins partially received in said grooves, means to retain said pins in said grooves, a hollow torque mandrel slidably received in said barrel, elongated grooves in the outer surface of said mandrel partially receiving said pins, said pins preventing rotation of said mandrel with respect to said barrel, means on the upper end of said mandrel for attaching the same to a drill string, a tubular connecting rod secured to the lower end of said mandrel and extending downwardly into said cylinder, a packing gland in the upper end of said cylinder slidably engaging said rod, an enlarged hammer portion on the upper end of said rod in said barrel providing an upwardly facing striking surface, a piston secured to the lower end of said rod and slidably received in said cylinder, an elongated tubular guide member on said piston extending downwardly into said sleeve, packing means in the upper end of said sleeve slidably engaging said guide member, an annular shoulder on said piston, annularly spaced abutments on said piston axially spaced above said shoulder, a split piston ring on said piston movable between said annular shoulder and said abutments and engaging the inner wall of said cylinder, axially disposed grooves in said piston inwardly of said ring and extending from said shoulder to a point above said abutments and axially disposed grooves in the inner wall of said cylinder extending from a point intermediate the length of said cylinder to the upper end, whereby upon application of an upward force to said mandrel said piston will move upwardly in said cylinder to compress fluid in said cylinder above said piston ring and accumulate energy in the drill string and upon said piston ring reaching the grooves in the cylinder wall pressure in the upper portion of said cylinder will be suddenly released thereby releasing the energy accumulated in the drill string to cause rapid upward movement of said hammer portion and engagement of said striking surface with said impact surface to apply an upward jarring force to a well device secured to said sleeve.

3. A iuid pressure one way jar comprising an upper elongated tubular member providing a torque barrel, a cylinder removably secured to the lower end of said barrel, an elongated sleeve secured to the lower end of said cylinder, means on the lower end of said sleeve for attaching the same to a well device, a reduced portion in the upper end of said barrel providing a downwardly facing impact surface, a hollow torque mandrel slidably received in said barrel, means to prevent rotation of said mandrel with respect to said barrel, means on the upper end of said mandrel for attaching the same to a drill string, a tubular connecting rod secured to the lower end of said mandrel and extending downwardly into said cylinder, a packing gland lin the upper end of said cylinder slidably engaging said rod, an enlarged hammer portion on the upper end of said rod in said barrel providing an upwardly facing striking surface, a piston secured to the lower end of said rod and slidably received in said cylinder, an elongated tubular guide member on said piston extending downwardly into said sleeve, packing means in the upper end of said sleeve slidably engaging said guide member, an 'annular shoulder on said piston, annularly spaced abutments on said piston axially spaced above said shoulder, a split piston ring on said piston movable between said annular shoulder and said abutments and engaging the inner wall of said cylinder, axially disposed grooves in said piston inwardly of said ring and extending from said shoulder to a point above said abutments and axially disposed grooves in the inner wall of said cylinder extending from a point intermediate the length of said cylinder to the upper end, whereby upon application of an upward force to said mandrel said piston will move upwardly in said cylinder to compress fluid in said cylinder above said piston ring and accumulate energy in the drill string and upon said piston ring reaching the grooves in the cylinder wall pressure in the upper portion of said cylinder will be suddenly released thereby releasing the energy accumulated in the drill.-

string to cause rapid upward movement of said hammer portion and engagement of said striking surface with said impact surface to apply an upward jarring force to a well device secured to said sleeve.

4. A uid pressure one way jar comprising an upper elongated tubular member providing a torque barrel, a cylinder removably secured to the lower end of said barrel, an elongated sleeve secured to the lower end of said cylinder, means on the lower end of said sleeve for attaching the same to a well device, a reduced portion in the upper end of said barrel providing a downwardly facing impact surface, a hollow torque mandrel slidably received in said barrel, means to prevent rotation of said mandrel with respect to said barrel, means on the upper end of said mandrel for attaching the same to a drill string, a tubular connecting rod secured to the lower end of said mandrel and extending downwardly into said cylinder, an enlarged hammer portion on the upper end of said rod in said barrelV providing an upwardly facing striking surface, a piston secured to the lower end of said rod and slidably received in said cylinder, an elongated tubular guide member on said piston extending downwardly into said sleeve, an annular shoulder on said piston, annularly spaced abutments on said piston axially spaced above said shoulder, a split piston ring on said piston movable between said annular shoulder and said abutments and engaging the inner wall of said cylinder, axially disposed grooves in said piston inwardly of said ring and extending from said shoulder to a point above said abutments and axially disposed grooves in the inner wall of said cylinder terminating above the lower end of said cylinder, whereby upon application of an upward force to said mandrel said pistonV will move upwardly in said cylinder to compress fluid in said cylinder above said piston ring and accumulate energy in the drill string and upon said piston ring reaching the grooves in the cylinder wall pressure in the upper portion of said cylinder will be suddenly released thereby releasing the energy accumulated in the drill string to cause rapid upward movement of said hammer portion and engagement of said striking surface with said impact surface to apply an upward jarring force to a well device secured to said sleeve.

References Cited in the tile of this patent UNITED STATES PATENTS 1,535,935 McLean et al. Apr. 28, 1925 1,804,700 Maxwell May 12, 1931 2,122,751 Phipps July 5, 1938 2,338,093 Caldwell Jan. 4, 1944 2,645,459 Sutliif July 14, 1953 

